Electric clock.



J. J, MOORE. ELECTRIC CLOCK.

APPLICATION FILED JAN.10, 1913.

Patented Mar. 24, 1914 2 SHEETS-BREST 1.

JJ/Mmm J. J. MOORE.

ELECTRIC CLOCK.

APPLIOATION FILED 1.411,10, 1913.

Patented Mar. 24, 1914,

z SHEETS-SHEET 2.

www :IJ/#dora i UNITED sTATEs PATENT oEEroE.

\ JOHN J. MOORE, 'OF oHAMBEasBURG, PENNSYLVANIA.

ELECTRIC CLOCK.

` T0 all whom. it may concern Be it known that I, JoH-N J. MOORE, acitizen of the United States, residing at Chambersburg, in the county ofFranklin and State of Pennsylvania, have invented new and usefulImprovements in Electric Clocks, of which the following is aspecification.

This invention relates 'to electric clocks adapted for use as domesticclocks, Atower clocks or the. master clocks yof systems, the main objectbeing to provide a prime mover for operating each clock through themedium of its balance staff, the prime mover being adapted to start theclock by giving an initial impulse to the said staff, and thereafter toimpart impulses thereto whenever its beat is below the normallength.

A further object is the provision of an" electric'circuit for \the saidprime mover and means provided in said circuit when it is desired togive an impulse to the balance staff, the said means being controlled bythe length of beat of the balance wheel staff.

A still further object is the provision of an electric strikingmechanism peculiarly adapted for use in connection with the clockoperating means. A Y v The invention consists in the features ofconstruction combination and arrangement of parts, hereinafter fullydescribed and claimed, reference being had to the accompanying drawings,in which:

Figure 1 is a front elevation; Fig. 2 is a side elevation; Fig. 3 is atransverse horizontal sectional view taken on the line 3 3 of Fig. 1: F4 is a fragmentary sectional view of the balance staff and crown wheelshowing the means for operating the latter;

Fig. is a plan view of the circuit closing governor, the balance stafi'lbeing shown 'in section, during the impulse beat of the staff; Fig. 6 isa similar view showing the governor in inoperative position as causedduring the reverse beat of the balance staff; and, Fig. 7 is a detail,fragmentary plan view of thc contact arms of the striking mechanism andthe means for mounting the same.

Referring to the drawings, and in particular to Figs. 2 and 3, 1 and 2'designates the front and rear plates of the clock frame which-areconnected by spacing fastening bolts 3. A supporting b racket`4v issecured to. the plate 2 adjacent its .lower edge by means of a bolt 5which is mounted within Specication of Letters Patent.

Patented Mar. 24, 1914.'y

Application led January 10, 1913. Serial N o. 741,257.

a sleeve 6 o-f insulating material, the latter being disposed within anopening in the plate and serving to insulate the said bracket from theplate. In this position the bracket extends inwardly to a. point aboutmidway of the clock frame where it is pro- Y vided with a verticallyadjustable steel bearing screw 7 provided in its upper end with a recessfor'the reception ed end of the vertical'balance staffl 8, the upper endof which is mounted within the recess in the lower end of a similaradjustable bearingscrew 9, which latter is mounted within a centralopening in lthe crossV bar 10 whose down-bent ends 11 and 12 are securedto the plates 1 and 2 of the frame of the lower pointby means of theclamping screws 13 and 14,

respectively, the said screws being surrounded by insulating sleeves 15and 16 so as to insulate the cross bar from the frame plates. The usualbalance wheel 17 is fixedly secured to the balance staff centrallythereof, and a hair spring 18 surrounds the upper end of the said staff,having its inner end fixed to the stalf and its outer end secured to theattaching stud 19 depending from the insulated cross bar 10. A bearingbracket 20 is attached to the rear plate 2 of the frame by means o-f theclamping screw 21 and is insulated therefrom by the collar 22ofpnonconducting material, and extends inwardly past the balance'stafl",its end being bent laterally in front of the said staff so as to supportthe inner end of a horizontal arbor 23 whose outer end is pivotallymounted, as

at 24, in an opening in the front plate. rlfhis 1 arbor 23 is disposedso that its longitudinal axis intersects the axis of the balance staff,and has ixedly mounted thereon, adjacent its inner end, the crown wheel25 provided with the beveled teeth 26 on its inner edge` An actuatingpin :27, having a sleeve 28 of insulating material surrounding itshorizontal portion 29, is mounted within a transverse opening 30 in thebalance staff immediately below the lower 'edge of the crown wheel sothat its upwardly bent, outer portion 31 is adapted to engage thestraight faces 32 of the teeth 26 during the'co-ntraction movement ofthe hairspring or what may be termed the reverse beat of the-balancestaff. A second actuating` member 33 ias its horizontal portion 34mounted in a transverse opening 35 in the staff immedil ately above theupper 'odge of the crown staff.

wheel and is angularly disposed with respect to the first-named member27 so that its down-bent engaging portion 36 will engage the saidstraight faces of the teeth 2G during the impulse beat of the balancestaff caused byy expansion of the hair spring. The minute hand post 37passes through an opening in the front plate 1 of the frame at 38 andhas' its inner end pivoted, as at 38, in a bearing recess provided inthe upper portion. of an upwardly bent supporting bracket 39 Whose lowerend 40 is secured to the plate 1 by means of the clamping screw 41 and*is in electrical connection therewith. The minute hand operating gearwheel 42 is mounted upon the post 37 adjacent the inner face of thefront plate 1 and is held in frictional engagement therewith so as torotate the same by engagement of the spring washer 43 with a cross pin44 extending transversely through the said post 37 with its convex face45. An engaging lmember 46 is secured to the arbor 23 adjacent the frontplate 1 and is so positioned radially with respect to the said arborthat its outwardly bent, horizontal portion 47 is adapted to enga ge thegear wheel 42 between the adjacent teeth thereof so as to impart slightmovement tothe same at each rotation of the said arbor 23. A pairofvertically spaced electro-magnets 48 and 49 are suit ably secured to therear plate 2 of thecloek frame so that the outer ends of their cores 50and 51 are in magnetic connection by means of the bar 52. A disk 53 isformed on the balance staff between the balance wheel 17 and the lowerend of the staff so as to rotate in a horizontal plane, and has attachedto one edge thereof the medial por'- tion of a vertically extendingarmature plate 54, whose end portions 55 and 56 are adapted to pass inclose proximity to the inner ends of the magnet cores 50 and 51,respectively, during oscillation of the balance A binding post 57insulated from the bracket by the non-conducting sleeve 57a is securedto the supporting bracket 4 adjacent its outer or attached end, and isprovided with an upwardly protruding contact point 58 disposed above thelevel of the said bracket. A circuit closing member 59. is pivoted tothe bracket 4 by means of a vertical bolt 60 which extends through thecylindrical body portion thereof. 'A laterally eX- tending contact armG2 is formed on the cylindrical body 61 of the member so as to extendoutwardly over the contact point 58, which latter is locatedl in thepath of hori- Zontal movement of the said arm. A pair of verticallyspaced, angularly disposed actuating arms 63 and 64 are formed on thebody 61 of the member 59 so as to extend inwardly therefrom. Anactuating member -G5 is secured to the balance staff adjacent its lowerend. The down-bent portion 66 `the crown gear 25,

of the said member is adapted to engage the operating arm 63 of thecircuit closing member upon oscillation of the balance staff caused bythe contraction of the hair spring 18. A second. actuating member 67 issecured to the balance staff above the firstnamed member (35 at 'ihorizontal angle to .the same. The down-bent end portion 69 of theactuating member 67 is adapted to engageV the operating arm 64 of thecircuit closing member upon oscillation of the balance stafl.l in itsimpulse beat in the direction of the arrow a in Fig. 5, as caused by theexpansion of the hair spring. i A binding post 70 is attached to thefront plate 1 of the clock frame adjacent its lower edge and is inelectrical connection therewith. A suitable source of electric supply 71has one of itsy electrodes 72 connected by means of a conductor 73 tothe binding post 70.

The electrode 74 of the said source is connected by means of a suitableconductor 75 to the electro-magnet 48. which is connected in series withthe other electro-magnet 49. The latter electro-magnet is then connectedby means of a conductor 76 to the binding post 57 carried by thesupporting bracket 4. It is to be understood that the hour hand sleeve77, which is shown in Fig. 1, is connected to the minute hand gear wheel42 by a suitable train of gears, the gear wheel 78 forming a part ofthis train, being the only one shown. It is to be understood that thehair spring 18 is so adjusted with relation to the actuating members and67 on the balance sta, that the latter will always come to rest, whenthe electric circuit is opened for any cause, in such a position thatthe contact arm 62 of the circuit closing device will be in'engagementwith the contact point 58. The actuating members 33 and 27, also, shouldbe disposed out of engagement with the teeth of A when the balance staffis at rest. Thus, when the electric circuit is again closed, an initialimpulse will be imparted to the balance staff due to the energization ofthe electro-magnets 48 and 49, after the balance -staif has beenmanually oseillated to bring the actuating .member 33 into engagementwith the teeth of the crown wheel 35.

In the operation 0f the time mechanism of the clock, the balance staffwill pulsate to beat regularly after it has been started, as justdescribed. The alternate expansion and contraction of' the hair spring18 during the impulse and reverse beats o-f the balance staff will causethe actuating members 65 and 67 to oscillate past the circuit closingmember 59. As shown in Fig. 5, the balance staff is turning in thedirection of the arrow a during its impulse beat, the actuating member67 having'just engaged the operat ing arm 64 of the circuit closer so asto swing posite direction in its reverse beat as indicated by the arrowb in Fig. 6, the member 67, or rather its portion 69 will clear the arm64. During this beat, in case the balance staff is pulsating up to itsnormal length of stroke, the member (i5 will engage the operating arm 63of the circuit closer so as to swing the contact arm 62 in the directionof the arrow c out of engagement with the contact point 58, so that,when the actuating member 33 is brought into engagement with the teethof the crown wheel with the next succeeding impulse beat of the balancestaff, the circuit closer will be in open position. Just as soon as thebeat of the balance staff becomes shorter than its normal length, themember 65 will fail to oscillate tar enough, during one of the reversebeats, to engage the operating arm 03 .of the -circuit closer so as tothrow the contact arm G2 out of Vengagement with the contact point 58.Therefore, as the actuating member' engages the teeth of the crownwheel, during the next successive impulse beat of the balance statt, thecircuit closer will be in closed position, thus permitting the currentto pass from the positive pole72 of the source of electrical supply 7lthrough the conductor 73, binding post 70, the frontplate l of theframe, arbor 23, crown 'wheel 25, actuating member 33, and the balancestatt 8 down to the bearing screw 7, whence it will pass through thebracket arm 4, the member 59 and its contact arm 62 to the contact point58. From the contact point 58 and the binding post 57 to which it isattached, the current will pass through the conductor 5G,electro-magnets 49 and 48 and conductor 75 back to the source 71 whereit is connected to the negative pole 74. The magnets 48 and 49 will thusbe energized when the armature 54 is yin suitable proximity to the same.so

that a. renewing impulse will be imparted to the balance stati". Thisoperation will continue as long as the battery or other suitable sourceof supply of electrical current 7l is in circuitwith the clock, or untilthe battery has become exhausted.

An important feature of the construction is the provision' of the disk53 on the balance staff which has the armature 54 attached thereto. Thisrenders the movement given the stati' by attraction of they armaturewhen the magnet is energized smooth and free, witho-ut the jerk whichwould be caused in case4 the armature .came in direct contact with themagnets as in the case ot' a reciprocating armature.

Thus far, the time operating mechanism of the clock has been dealt with,but I will IlOW proceed with a description of the striking mechanismwhich is dependent upon the previously described structure.

An inwardly extending post or support 79 .formed of hard rubber,'ber orsome such insulating material, is secured at its outer end to the rearplate 2 of the clock frame bv means of the clamping screw 80, and hasits v inner end, which extends slightly past the Center of the frame,reduced, as at 81. A pair of relatively spaced contact arms 82 and 83are enlarged, as at 84 and 85 adjacent their outer ends, and-providedwith angular openings in these enlarged portions for the reception of ablock 86 of insulating material, which is mounted for oscillation upon'the reduced po-rtion 81 of the support 79. This block 86 serves toinsulate 'the said arms effectively and to cause simultaneous operationof both arms. A clamping screw 87 is inserted into a threaded recess inthe end of the reduced portion 81 of the support 79 so as to secure theblock 80, with its attached conta-ct arms, in position thereupon, andwhich at the same time permits oscillation of the same upon the pivotthus formed. The outer end portion 88 of the arm 82 is shorter than thecorresponding portion of the other arm yand is adapted to bear againstthe upper surface of the angular stopmember 90 carried by the support79. A helical spring 92 surrounds the support 79 adjacent the contactarm 82 and has -one end secured to said arm and the other to the stopmember 90 so as to normally main` tain the inner ends of the contactarms in their uppermost position with the portion 88 of the arm 82 inengagement with the said stop member 90. A movable postor arbor 93 hasone end journaled, as at 94, in the plate 2 adjacent the support 79, andhas its other end jo-.urnaled in the plate 1, as at 95. the reducedportie-n 9G at this end of the post being extended outwardly past theouter face of the plate 1. secured to the movable post 93 adjacent theend portion 89 of the Contact arm 83 and has a lateral projection 98adapted to engage the under. edge of theiaid portion 89 of thev contactarm so as to support the arms 82 and 83 in such a'position against thetension ot the spring 92 that the beveled projection 99 formed on theouter face ofthe arm 82 at its inner end is disposed medially below thepath of movement of the operating lug 100 extending laterally from thebalance statt above the disk 53. In this position, the pon tion 88 ofthe arm 82 is slightly spaced from' the stop member 90. An angulartripping member 101 carried by the minute hand post 37 is provided witha. lateral extension 102 adapted to engage the under edge of an in-ywardly extending tripping arm 103 carried by the movable post 93, whenthe minute hand `arrives at the hour mark and in so doing A lifter pin97 is I cured to its inner lowers the lifter pin 97 to permit Ltheportion 89 of the contact arm 83 to drop and allow vthe portion 88 ofthe other arm to rest upon the stop member 90. When the contact arms 82and 83 are in this position, the beveled projection 99 on the outer endof the former is located in the path of movement of the lug 100 and isadapted to be engaged thereby to force the extremity of the arm 82 overinto engagement with a laterally extending contact pin 104 passingthrough the outer arm 83 adjacent its extremity. An auxiliarv orreleasing member 105 is provided on the'inwardly projecting portion 106ot the minute hand post. This member com-A prises a lateral portion 107secured to the portion 106 of the post, a longitudinally extendingportion 108, and an inwardly extending finger, the latter being adaptedto engage the surface of -the adjacent portion of the contact pin 104 soas to hold the Contact arms 82 and 33 below the position inwhich theenlargement 99 is inthe path of the lug 100, thus maintaining theportion 88 ot the contact arm 82 slightly above the stop 90. In theinstant the minute hand arrives at the hour mark, the finger 109 movesout of engagement with the portion 110 of the contact pin 104 so as torelease. the contact arms and allow them to be thrown upward into theiroperative position by the action of the spring 92, the said portion 88of the arm 82 resting upon the stop 90 in this position and preventingundue upward movement of the conta-ct arm.

The arcuate rack member 111 is pivoted to an inward extension 112 lo1the front plate 1 by means of the pivot bolt 113. This member 111 isprovided on the upper portion ot its periphery 4with a plurality ofoutwardly raking ratchet teeth 114, a cut-away portion or depression 115being provided adjacent the outermost. tooth for the reception ot'. theactive point 116 o1 a pawl 117 which is lixedly connected to theprotruding, reduced extremity 96 of the movable post 93, as at 118, whenthe striking mechanism is inoperative. A plurality of downwardly rakingrack teeth 119 are provided upon t-he lower, outer portion of the member111. fl`hese teeth are adapted to be engaged by an operating member 120which is pivoted, at 121, to a lateral arm 122 which is secured ixedlyat 123 to the outwardly projecting, reduced portion 124 of a movablearbor 125 pivoted between the front and rear plates 102 of the frame,yas at 126 and 127. The member 120 is normally held in position forengagement with the said teeth by leans of a. spring 128 secured to thearm 122. An arm 129 projecting inwardly from the central portion of thearbor 125 has seend the central portion of a transversely extendingarmature 130 whose end portions 131 and 132 are disposed above and 134so as to portion or linger' ing` mechanism for the cores of a pair ofelectro-magnetsl 133 be attracted by the same when the magnets areenergized. These electro-magnets are supported upon a transverse plate135 secured to the frame plates at either end by means of suitablescrews 136 and 137. A downwardly curved hammer arm 138 is provided onthe movable arbor 125 and is adapted tost-rike the extremity of theupper portion 140 of the striking lever 141 which is secured to atransverse arbor 142 in suitable proximity to the bell 143, its endsbeing pivo-tally mounted in the frame plates 1 and 2, as at 144 and 145.A stop member 146 extends inwardly from the frame plate 2 and is adaptedto engage the under surface of a inger 147 carried by the said arbor 142so as .to limit the downward movement of the main portion of the lever141 which bearsthe striking hammer 148. A helical spring 149 encircles aportion of the movable post 89 and has one extremity attached to theplate 2 and the other extremity attached to the curved hammer 138 ytomaintain the said post in such position that the armature 130 isnormally spaced from the cores of the electro-magnets 133 and 134. Aninwardly extending adjuster arm 150 is formed on the arcuate member 111adjacent its point of pivotal connection and has its extremity inbent,as at 151, for engagement with one of the active faces 152 of the stepcam 153 which is iixedly secured to the hour hand therewith, the latterbeing movably mounted upon the minute hand post 37. The contact arm 83which is insulated from the contact arm 82 is connected by means of aconductor 155 with the electro-magnet 134, which is in turn connected inseries with the electro-magnet 133`by mea-ns of the conductor 156, andthe magnet 133 is connected by means of the conductor'157 with one poleot a suitable source of electrical supply or battery 158, Vthe oppositepole of the battery being connected by means or' the conductor 159 withthe contact arm 82.

,lt is to be understood that I may utilize' the source ot supply 71 forthe clock operatthel striking mechanism by connecting theelectro-magnets and contact arms just described in parallel with theoperating circuit.

ln the operation of the striking mechanism, it will be seen that. whenthe minute hand arrives approximately at the hour mark, the angularmember 101 will raise the arm 103 attached to the movable post 93, thuslowering the member 97 and permitting the Contact arms 82 and 83 to beturned upon their pivot so'that the contact pin 104 rises-intoengagement with the inger 109 of the auxiliary tripping member 105carried by the inner end sleeve 154 so as to rotate' use in connectionwith of the minute hand post..l This motion of the movable post causes'the pawl117 to be moved so that its engaging extremity 116 rises fromthe recess 115 and permits the member 111 to lgravitate into itslowermost position, the inbent extremity 151 of thearm 150 being raisedinto contact with one of the active faces 152 of the step cam 153. This'arm 150 determines by the extent of its upward movement, the number ofratchet teeth 154 which will be passed over by the pawl 117. When .theminute hand arrives exactly at the hour mark, the finger 109 of theauxiliary tripping device will be tliio'wn out of engagement with theportion 108 of the contact pin 104 so as-to allow the contact arms tomove upwardly into their operative position, this motion being limitedby engagement of the stop 90 with the portion 88 of the arm 82. At eachpulsation or beat of the balance staff, thelug 100 will engage onebeveled face of the enlargement 99 formed on the extremity of thecontact arm 82 so as to force the said arm into engagement with thecontact pin 104 of the coacting arm. At each of. these closingoperations,

4the electrical circuit will be closed through the magnets 133 and 134so as to attract the armature 130 and thus cause the hammer 138 tostrike the anvil 139 and thereby to cause the striking hammer 148 tostrike the bell 143. At the same time the arm 122 is moved upwardly soas to bring the member 120 into engagement with one of the rack teeth119. The throw of the armature arm is sufficient in length to impartmovement to the member 120 necessary to force the armature memberupwardly so that the extremity 116 of the pawl 117 will fall into asecond notch. As the lug 100 moves out of engagement with theenlargement 99 on the Contact 82, the circuit will be broken and thearmature supporting arm 129 will rise due to the action of the spring149, thus causing the member 120 to drop to a second notch on the rack119. Thus it will be, seenthat each pulsation of the balance staff willcause a bell stroke, and the number of teeth over which the pawl 117passes before it drops in the recess 115 will determine the number ofstrokes. When the extremity 116 of the pawl 117 finally drops in therecess 115, the angular member 101 carried by the minute hand postwill'be out of the path of the arm 103, thus allowing this arm togravitate into its lowermost position and causing the lifter pin 97 toraise the portion 89 of the contact arm 83, thus forcing the contactarms into their lowermost inoperative position against the action of thespring 92, where they remain until an hour has elapsed and it is timefor a repetition of the striking operation just described.

Vhat is claimed is 1. In a clock of ther class described, the- )alancestall' journaled between said cross plates, of a supporting bracketcarried by one of said plates and insulated therefrom, an insulatedcross bar connecting said frame lates in spaced relation to saidbrackets, a bar and bracket and being in electrical con- 7o nectio-ntherewith, an armature carried by said balance staH, an electro-magnetattached to the frame in suitable proximity to the path of movement ofsaid armature, a contact point attached to said bracket and insulatedtherefrom, electrical connection between the said contact point andelectromagnet, a source of electrical supply connected with theelectro-magnets and one of the frame plates, a circuit closer pivoted tosaid bracket and having a contact arm enlgageablewith the insulatedcontact point,

means for electrically connecting said balance staff with the frameplate to which the source of electrical supply is connected during theimpulse beat of the balance staff, and means provided on the balancestaff for actuating the circuit closer during the impulse beat of thebalance staif to throw the contact arm carried by the circuit closeronto said contact point.

2. In a clock of the class described, the combination with a pair ofspaced frame plates, of a supporting bracket carried by one of saidplates' and insulated therefrom, an insulated cross bar connecting saidframe plates in spaced relation to said brackets, a balance staffjournaled between said cross bar and bracket and being in electricalconnection therewith, an armature carried by said balance staff, anelectro-magnet attached to the frame in suitable proximity to the pathof movement of said armature, a contact point attached to said bracketand insulated therefrom, electrical connection between the said contactpoint and electromagnet, a source of electrical supply connected withthe electro-magnets and one of the frame plates, a circuit closerpivoted to said bracket and having a contact arm engageable with theinsulated contactvpoint, means for electrically connecting said balancestaff with the frame plate to which the source of electrical supply isconnected during the impulse beat of the balance staff, means providedon the balance staif for acl tuating the circuit closer during theimpulse beat of the balance staiil to throw the con-- tact arm carriedby thecircuit closer onto said contact point, and means provided uponthe balance staff for actuating the circuit closer so as to throw thecontact arm out of engagement with the contact point during/ eachreverse beat of the balance stal-l when the beat is normal in length,the latternamed actuating means being inoperative when the beat of thebalance staff is below normal length.

3. In a clock of the class described, the

combination with a pair of spaced frame plates, of a supporting bracketcarried by one of said plates and insulated therefrom, an insulatedcross bar connecting said frame plates in spaced relation to saidbrackets, a balance staff journaled between said cross bar and bracketand being in electrical connection therewith, an armature carried by-said balance sta, an electro-magnet atbeat of the balance staff tothrow the Contact arm carriedby the circuit ycloser onto said Contactpoint, a bearing bracket attached to the frame plate opposite to the oneto which the source of electrical supply is connected,

\ the said bracket being insulated from the plate to which it isattached, an arbor journaled between said bracket and the plate to whichthe source of supply is connected, said arbor being in electricalconnection with the last-named plate, a crown wheel iiXedly attached tosaid arbor, an actuating member carried by the balance staff inelectrical connection therewith and engageable with the said crown wheelduring the impulse beat of the balance staff to cause operation of thesame, a second actuating member insulated from the said balance staf andengageable with Jthe crown wheel at a` point diametrically opposite thefirst-named actuating member to cause operation thereof during thereverse beat of the balance staff, and means for operatively connectingsaid arbor with the time mechanism ofthe clock.

4. In a clock of the class described, the combination with a pair ofspaced frame plates, of a supporting bracket carried by one of saidplates and insulated therefrom, an insulated `cross bar connecting saidframe plates in spaced relation to said brackets, a balance stafljournaled between said cross bar and the bracket and being in electricalconnection therewith, an armature carried by said balance staff, anelectro-magnet attached to the frame in suitable proximity to the pathof movement of said armature, a contact point attached to said bracketand insulated therefrom, electrical connection between the said contactpoint and electromagnet, a source of electrical supply connected withthe electro-magnets and one of the frame plates, a circuit closerpivoted to said bracket and having a contact arm engageable with theinsulated contact point, and means provided on the balance staff foractuating the circuit. closer during the impulse beat of the balancestaff to throw the contact .arm carried by t-he circuit closer onto saidContact point, and means provided upon `the balance staff for actuatingthe circuit the contact arm'out of engagement with thecontact pointduring' closer so as to throw each reverse beat of the balance stan?when the beat is normal in length, the last-named actuating means beinginoperative when the beat of the balance staff is below normal length. v

5. In a `clock of the class described, the

combination with a frame, of a balance staff journaled therein, anarmature carried by said staff, an electro-magnet attached to the frameand disposed in suitable proximity to the path ofmovement of saidarmature, a

Contact point mounted upon the frame and insulated therefrom, electricalconnection be tween the said contact point and one terminal of theelectro-magnet, a source of electrical supply having one terminalconnected with the electro-magnet, means for connecting the otherterminal of the source electrically with the balance sta'l during eachimpulse beat of the latter, a circuit-closing member pivoted to theframe fo-r swinging movementin a plane disposed at right angles to theaxis of the balance'staff and having a contact arm engageable with thesaid contact point, a pair of angularly and longitudinally spaced armsextending laterally from the said contact member, an actuating memberprovided upon the balance staff for engagement with one of the said armsof the circuit-closing member duringthe impulse beat of the balancestaff to operate the circuit-closing member so as to move its contactarm into engagement with the said contact point, and a second actuatingmember carried by the balance staff and adapted for engagement with theother arm of the circuitclosing member during the reverse beat of thestaff when of normal length to operate the circuit-closer and move itscontact armout of engagement with the contact point.

In testimony whereof I aiiiX my signature in presence of two witnesses.

ARTHUR W. GILLAN, O. M. ORB.

